This apparatus and method involve the electronic generation of free radicals directly from water, or alternately from the waters of an aqueous fluid, the contents of which are required to be treated by oxidation/reduction reactions.
Aqueous free radicals are universally regarded as highly reactive reagents, useful in a wide variety of oxidation/reduction reactions. The most notable application of such free radical reactions to date is in wastewater treatment. These radicals have a potentially broader area of application for such purposes as desalination of water, the recovering of oxide ores from complex minerals in solution, water treatment in general and a host of other applications involving the chemical breakdown of suspended and/or dissolved mineral and organic compounds.
Aqueous free radicals are generally classified into two groups commonly referred to as primary free radicals and secondary free radicals. The primary free radicals include on the OH.sup.o and H.sup.o free radicals. The secondary free radicals include the O.sup.o radical and its variants. These variants comprise free radical complexes produced by the spontaneous combination of the free radicals with water or with each other. The basic family of aqueous free radicals includes H.sup.o, OH.sup.o, H.sub.2 O.sub.2.sup.o, HO.sub.2.sup.o, H.sub.3 O.sup.o, and O.sub.3.sup.o radicals. Other complex variants are known to exist. The H.sup.o and H.sub.3 O.sup.o radicals are regarded as weak reducing agents, while all other of the radicals are regarded as strong oxidizing agents.
These free radicals act to dismantle complex organic and mineral substances contained or dissolved in solution into constituents having insufficient chemical energy to react further with water. Such constituents are generally of the form of simple oxides, peroxides, hydroxides and the like, including also water and gases. With the exception of some of the gases formed, the constituents are passive, generally insoluble in water, and are therefore environmentally stable. Many of the reactants proceed by auto-oxidation through a free radical chain reaction mode resulting in an automatic recovery of the reagent radicals. Such recovered radicals continue to react with reactants in solution, freely complimenting the efficiency of the process. Free radicals usually react rapidly with the reactant materials and any excess radicals recombine to form water. Thus, free radicals provide a viable alternative to the use of chemical reagents in many treatment processes.
The difficulty posed until now for the generation of aqueous free radicals has been the requirement for high energy systems. Previously known methods for generating aqueous free radicals include the use of ultrasonic oscillation, gamma irradiation, high intensity ultraviolet light and high voltage electrical discharge. With the exception of the ultraviolet method which has already seen limited use in waste water treatment, such high energy methods have not had any practical applications.